
var timeout = 500;
var closetimer = 0;
var ddmenuitem = 0;

// open hidden layer
function mopen(id) {	
	// cancel close timer
	mcancelclosetime();

	// close old layer
	if (ddmenuitem) {
		ddmenuitem.style.visibility = "hidden";
	}

	// get new layer and show it
	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility = "visible";
}
// close showed layer
function mclose() {
	if (ddmenuitem) {
		ddmenuitem.style.visibility = "hidden";
	}
}

// go close timer
function mclosetime() {
	closetimer = window.setTimeout(mclose, timeout);
}

// cancel close timer
function mcancelclosetime() {
	if (closetimer) {
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

// close layer when click-out
document.onclick = mclose;

